Tibial prosthesis extractor and method for extracting a tibial implant

• US 4,459,985 A
• Filed: 03/04/1983
• Issued: 07/17/1984
• Est. Priority Date: 03/04/1983
• Status: Expired due to Term

• Current Assignee: Stryker Technologies Corporation
• Original Assignee: Howmedica Inc.
• Inventors: McKay, William F., Van Syckle, Peter B.
• Primary Examiner(s): Frinks, Ronald L.
• Application Number:
  US06/472,335
• Time in Patent Office: 501 Days
• Field of Search: 128/303 R, 128/92 EC, 128/92 E, 128/92 C, 128/83, 3/1.911, 3/1.91
• US Class Current: 606/100
• CPC Class Codes: A61F 2/461 of knees
• CPC Class Codes: A61F 2002/4619 for extraction
• CPC Class Codes: A61F 2002/4628 with linear motion along or rotating motion about an axis transverse to the instrument axis or to the implantation direction, e.g. clamping

Abstract

An extractor for dislodging an implanted tibial prosthesis comprising substantially parallel upper and lower members joined by a yoke, with the lower member comprising a pair of forked blades to insert under the tibial component and the upper member being adapted to receive means for applying upward dislodging force.

Claims

1. An extractor for dislodging an implanted tibial prosthesis having a tibial tray and stem,

said device comprising substantially parallel upper and lower member joined by a yoke at one end thereof,

said members being sufficiently spaced by said yoke to admit said tibial tray therebetween,

said lower member comprising a pair of forked blades for insertion between said tray and the proximal end of the tibia, straddling said stem,

and said upper member being adapted to receive means for applying upward dislodging force to said tray in substantially axial alignment with said stem to extract said prosthesis from said tibia.

2. The extractor of claim 1 wherein said upper member is adapted to attach an impact device thereto for applying said dislodging force.

3. The extractor of claim 1 having anchoring means for fixed securement to said tibial tray while said dislodging force is applied.

4. The extractor of claim 3 wherein said anchoring means is a pointed screw threaded therethrough for engaging a plastic insert in said tibial tray.

5. A method for extracting a tibial implant having a tibial tray and stem comprising

excising a layer of proximal tibial bone immediately below said tibial tray,

inserting fork means into the space so created between the tray and the proximal tibia surface, straddling said stem,

and transmitting impact shock to said tray through said fork means in a direction substantially coaxial with said stem.